Flying-machine level.



F. TEAL.

FLYING MACHINE LEVEL.

APPLICATION FILED APR. 19. 1918.

Patented Apr. 8,1919.

Invert zor' FRANK TEAL, 0F TROY, NEW YORK.

FLYING-MACHINE LEVEL.

Specification of Letters Patent.

Patented Apr. 8, 1919.

Application filed April 19, 1918. Serial No. 229,516.

To all whom it may concern:

Be it known that I, FRANx TEAL, a citizen of the United States, residing at Troy,

county of Rensselaer, and State of New York, have invented certain new and useful Improvements in Flying-Machine Levels, of which the following is a specification.

Reference may be had to the accompanying drawings, and the reference characters marked thereon, which form a part of this specification. Similar characters refer to similar parts in the several figures therern.

This invention relates to improvements in aeronautical clinometers or flying-machine levels, and is especially adapted for use upon aeroplanes.

The principal object of the invention is to afford information to an occupant of the machine of the angular position of the machine with respect to its normal level position.

Figure 1 of the drawings is a view showing in elevation my improved aeroplane level mounted upon a broken-away portion of an aeroplane with the aeroplane in normal level position.

Fig. 2 is a similar view with the aeroplane inclined to the right.

Fig. 3 is a cross-section of the same taken on the broken line 3-3 in Fig. 1.

Referring to the drawings wherein the invention is shown in preferred form, 1 represents a broken-away portion of a post, forming part of an aeroplane construction.

Upon this post is mounted a frame, 2, provided with a central opening, 3, and with a ball-runway, 4, of general rectangular form surrounding said central opening 3.

This frame is so mounted upon the post, 1, that the angles, 5, 6, 7, and 8, in the runway are respectively at the top, bottom and opposite sides of the runway, when the aeroplane is in normal level position, as shown in Fig. 1.

A ball, 9, is adapted to travel freely along said runway, 4, said ball being seated from time to time in whichever of the angles, 5, 6, 7, and 8, is lowermost.

Within the opening, ordinary spirit-level, 10, stantially in line with and 8, of the runway,

3, is mounted an which extends subthe side angles, 7

4that is in horizontal position when the aeroplane is in normal level position. The spirit-level may be thus mounted in any known manner.

I have shown the level, 10, mounted upon the frame, 2, by means of a bracket or frame, 11, whereby the level, 10, is supported in fixed relation to the frame, 2, and to the post, 1.

The post, 1, represents a portion of an aeroplane construction, such that the device above described will be located in front of an occupant of the machine, preferably the pilot, and the front of the frame,

2, may be formed by aplate of glass, 12, permlttlng observation of the spirit-level,

10, ball-runway, 4, and ball, 9. 1

The back, 13, of the frame may also be made of glass, or the whole frame may be made of glass if desired. 7

When the aeroplane is in normal level position, the bubble, 14, of the spirit-level, 10, will be in middle position, and the ball, 9, will be in the angle, 6, in the runway, 4, directly below the bubble.

Slight inclination of the aeroplane to either side will be indicated by corresponding displacement of the bubble, 14, but without displacement of the ball, 9, with respect to the angle, 6, in which it is seated.

Any great degree of tipping of the aeroplane, however, to one side or the other throws the bubble, 14, to one end or the other of the spirit-level, where it is useless for observation purposes.

The position of the aeroplane and approximately the degree to which it is inclined can, however, be readily determined by the occupant by noting the position of the ball, 9, with relation to the level, 10. Thus if the machine be completely inverted the spirit-level, 10, will appear inverted above the ball, 9. If the machine be tipped considerably to the right, its position will be quickly indicated to the occupant by the position of the ball, 9, with respect to the spirit-level, as shown in Fig. 2.

In a similar manner various other positions of the machine will be indicated to the occupant.

By the use of my invention, an occupant of an aeroplane when out of sight of the earth or other external objects can at a glance at once determine slight angular variations in the position of his machine, and when such variation is sufficient to cause the ball, 9, to travel from the angle, 6, to one of the other angles, the approximate angular position of the machine can be at once determined by noting the position of the ball, 9, with respect to the position of the spirit-level.

The occupant of the machine is thus given quick information which enables him to right the machine whenever the machine is dangerously inclined or inverted.

What I claim as new and desire to secure by Letters Patent is:

1. In a device of the class described and in combination, a level-tube; a frame provided with a ball-runway extending in general rectangular path around said leveltube,

said level-tube being mounted in fixed relation to said runway and in line with two oppositely disposed angles in said runway; and a ball free to travel around said runway.

2. In a device of the class described and in combination, a rectangular frame provided with a central opening, and a ballrunway extending around said opening; a

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, 7

ball free to travel around said runway; and a level-tube mounted diagonally of said frame within said central opening.

3. The combination; of a level-tube; a frame provided with a ball-runway extending in a general rectangular path around said level-tube, said level-tube being mounted in fixed relation to said frame with said level-tube horizontal and the angles in said runway above, below and at the ends of said tube; and a ball free to travel along said runway.

4. The combination, of a frame prov ded with a ball-runway of general rectangular path with angles in said runway at its top, bottom and opposite sides when said frame is level; and a ball free to travel along said runway. V

In testimony whereof I have hereimto'set my hand this 17th day of April, 1918.

FRANK TEAL.

Washington, D. 0. 1 

